[THIS WEEK IN SOCCER: March 17-23] Barcelona needs a result at Real Madrid Sunday in Spain's Clasico to stay in the hunt for La Liga title. The Chelsea-Arsenal
London derby also has title implications in the Premier League, while Concacaf Champions League action continues for three MLS clubs.

TUESDAY, March
18: The atmosphere should be -- well -- caliente at the Estadio Caliente for Tijuana-LA Galaxy (live on Fox Sports 2 and Galavision at 10
p.m. ET), the first of three MLS-Liga MX second legs in the Concacaf Champions League quarterfinals. The Galaxy carries a 1-0 lead across the border but faces a tough challenge against Xolos, which
had a 17-game unbeaten streak on the artificial turf at home snapped three weeks ago.

WEDNESDAY, March 19: -- MLS clubs Sporting Kansas City and San Jose both face huge tasks on the road at altitude against the two best teams in Mexico's Torneo
Clausura in the Concacaf Champions League quarterfinal return legs. Sporting KC holds a 1-0 lead over Cruz Azul but must face La Maquina, which leads the Liga MX with a 9-1-1 record, in Mexico
City (live on Fox Sports 2 and Galavision at 8 p.m. ET). The Earthquakes managed a 1-1 tie against Toluca in their first leg to give them some hope for the trek to La Bombanera, the home of the
Diablos Rojos, who are second in the Liga MX just three points behind Cruz Azul (live on Fox Sports 2 and UDN at 10 p.m. ET).

-- David Moyes' future could be on the line at Manchester United as it attempts to make up a two-goal deficit against Olympiakos at Old Trafford. United, a 2-0 loser in Piraeus, was the only seeded team to lose
its away leg in the UEFA Champions League round of 16. The game comes only three days after United's embarrassing 3-0 loss at home to Liverpool that left it in seventh place in the Premier League.

SATURDAY, March 22: -- A slate of eight MLS games features home openers for Colorado, Columbus, Montreal
(at Olympic Stadium), New England, Real Salt Lake and Toronto FC. In the day's top game, Real Salt Lake faces the LA Galaxy (live on NBCSN at 4 p.m. ET) in a rematch of their opener two weeks ago RSL
won, 1-0, on a late Joao Plata goal.

-- USL PRO opens its fourth season with two intriguing matchups: defending champion Orlando City travels to
2012 champion Charleston, and LA Galaxy II hosts Orange County Blues in the first game for the LA Galaxy's new USL PRO team.

-- Chelsea's 1-0 loss to Aston Villa on Sunday gave Arsenal a
lifeline heading into the London derby (live on NBCSN at 8:45 a.m. ET). The Gunners, who led the EPL for much of the fall, are now tied with Liverpool four
points behind leader Chelsea with both second-place teams holding a game in hand. (Fourth-place Manchester City is two points behind Arsenal and Liverpool and six behind Chelsea but with two games in
hand on the second-place teams and three on the leader.)

SUNDAY, March 23: Real Madrid can all but eliminate Barcelona from La Liga race with a
win over the defending champions in Spain's Clasico at the Estadio Santiago Bernabeu (live on beIN Sports at 1 p.m. ET). Real Madrid begins the week with a
three-point lead over second-place Atletico and four-point lead over Barca.